The win - Sydney's fourth of the campaign - lifts the Sky Blues three points clear of the Wanderers and into eighth spot on the table.

Mallia, who has made several A-League appearances for the senior Sydney team, gave his side the perfect start on 10 minutes.

He accepted a lovely pass from Tom Slater to tuck home the ball on the second attempt after his first effort was partially saved by goalkeeper Aaron Liddell.

The Wanderers should have drawn level in the 26th minute when Jaushua Sotirio teed up striker Mark Cindric with a layoff from the by-line.

But Cindric was not quick enough on the trigger and his meekly struck shot was deflected for a corner.

Sydney responded to that scare with their second goal, via the penalty spot, minutes later.

And again Mallia was in the thick of it.

He pursued a long through-ball to go one-on-one with Liddell inside the box.

The two arrived simultaneously and Mallia was quickest to react with a header after the ball spewed in the air.

The referee ruled Liddell fouled the striker as he attempted to nod the ball into an empty net, leaving Jared Lum to fire home the penalty for a 2-0 advantage.

The visitors almost pinched a goal back right on the stroke of half-time only for Sydney keeper Anthony Bouzanis to deny Jake McGing from close range.

But the Wanderers didn't have to wait long for a reward.

Three minutes after the resumption Zac Elrich displayed tremendous speed and determination to outstrip the Sydney defence and find the back of the net with a firmly hit shot into the bottom right corner.

The Wanderers pushed forward in search of an equaliser but were undone by a defensive blunder 10 minutes from time.

Mallia seized on a poor back pass, winning the initial challenge with the keeper before sweeping the ball into a vacant net.

Terry Antonis completed the scoring, finishing off some terrific work from Alex Urosevski to bury Sydney's fourth at the death.